Air beake



(No Model.) 2 Sheets,Sheet 1.

J. J. NEP. AIR BRAKE. No. 602,094. Patented Apr. 12,1898.

M1 ii .22 \llllllllllllll WITNESSES: I INVP OR 1 11w: ATTORNEY (NoModel.) 2 SheetsSheet 2.

J; J. NEP. AIR BRAKE.

N0.60Z,094; I PatentedApr. 12,1898.

WITNESSES: INVENTOR ATTORNEY JOHN NEF, OF NEW YORK, N. Y.

Price.

AIR-BRAKE.

SPECIFICATION forming part of Letters Patent No. 602,094, dated April12, 1898.

Application filed July 31, 1897. Serial No. 646,679. (No model.)

7 To all whom it may concern:

Be it known that I, JOHN J. NEF, a citizen of the United States,residing in the city,

county, andState of New York, have invented a new and useful Improvementin Air-Brakes, of which the following is a specification.

This invention relates to automatic pressure-governors, and has for itsobject the provision of efficient and reliable means for automaticallythrowing the pump used to supply fiuid under pressure, into and out ofaction, according as the fluid-pressure falls below or rises above acertain degree. This invention consists in a novel structure andarrangement of parts whereby a piston-rod is adapted by its movement inone direction to engage and in the other to disengage the pump and itsactuating mechanism, the said piston-rod being attached to two pistonsof different diameters, upon the smaller of which the fluid-pressureactsfat all times tending to keep the pump in operation, but upon thelarger the fluid-pressure is admitted or exhausted according as itsintensity is above orbelow a certain predetermined point, the admissionand exhaust to the larger piston being controlled by a valve, whichvalve is actuated in one direction by the action of the fluid-pressureupon a piston in the valve-chamber and in the other direction by aspring, the result being a Very compact and simple construction, and atthe same time one that is reliable and efficient.

In the drawings accompanying and forming a part of this'specification,Figure 1 is a general View showing the pump with an actuating mechanism,the governor, and a reservoir in which compressed fluid is stored. Fig.2 is a sectional view of the governor on a plane passing through thecenters of the pistons, this plane being parallel to the plane of theView shown in Fig. 1.

Similar characters of reference designate like parts in both figures.

This governer comprises, in a general way, two main parts, designated Aand B, respectively. One part,being that designated by A, is a compoundcylinder or, in other words,

' consists of two cylinders of' different diameters, preferably arrangedupon the same axis. In this compound cylinder are arranged two pistonsof diameters to correspond to the different bores of. the compoundcylinder, rigidly attachedl together and to a piston-rod, the movementof the pistons and rod operating to stop'and start the pump. The secondmain part above alluded to, designated generally by B, consists of avalve-chamber secured to the compound cylinder, said valvecharnberhaving a cylindrical portion in which is fitted a piston adapted to beacted upon source of supply.

In the preferred form of my invention here- I in shown and described thepart which I have designated generally by A comprises the compoundcylinder 6, the head 7 for the small end, the head 8 and 'stuffing-box 9for the larger end, the pistons 3 and 4 and rod 5, together with anyapproved form of packing and means forlconnecting the pistons and rod.

The valve-chamber and its accessories, designated in a general way by13, comprises the main Valve-chamber casting 12, the valve 13, thepiston 14, the hollow piston-rod 15, the spring 16, together with thehead 17 and adjusting-screw 18. The valve-chamber 12 is secured to thecompound cylinder 6 by means of screws or bolts 20 20.

As shown in the drawings, the piston in the compound cylinder 6 is inits extreme right position, the operating mechanism of the pumpconnected through clutch 22, and the pump in operation. The parts willremain in this position and the pump will remain in operation until thepressure of fluid in the reservoir rises above a predetermined point,when the pressure on the piston 14 in valve-chamber 12 overcomes thetension of spring 16 and moves the piston to the left, carrying with itvalve 13, thereby opening communication between the valve-chamber 12 andthe larger of the two cylinders .2, thus admitting reservoir pressureinto the cylinder 2 where it acts upon the When the pressure in thereservoir falls below a predetermined point, the spring 16 will overcomesuch pressure acting upon'the piston 14 and move it to the right,carrying the valve 13 to the position shown in Fig. 2,

closing connection between the valve-cham her and cylinder 2 and openingcommunication between cylinder 2 and' the exhaust 281 The air fromcylinder 2 having exhausted, the

piston 4 is forced to its extreme right position by the pressure incylinder 1 on piston-3:andthe pump put in operation, as alreadydescribed.

What I claim is- 1. The combinationin:anaiirbrake system of atpump andpumpoperating mechanism of a compound air-cylinder comprising twocylinders-of cliferent diameteraapiston within said: compound cylinderhaving heads of diflerent diameters corresponding with the boresof-saidcompoundcylindera'valve-chamber-im open: communication with thesmaller cylinder and having: a port communicating with thelargercylinderandr an exhaust-port,

aivalveinsaid ValVechamber, andm'eansaact- 7 ing. under variations inair-pressure foropcrating said: valve: toalternately openz and;

close-said larger cylinder tothevalve-chame her and the exhaust,substantially as de*-- 1 scribed;

53'; The combinationin an air-brake system ot a pump and pump-operatingmechanism,

,of a compound air-cylinder comprising two cylinders ofdifterentdiameters,apiston within said compound cylinder having heads ofdifferent diameters corresponding with the bores of said compoundcylinder, a Valvechamber having open communication with the smaller ofsaid cylinders, and having a port connecting with the larger of saidcylinders, an exhaust-port, and a valve controlling said ports wherebyair is admitted to the larger cylinder to move the piston in one di-,rection and exhausted therefrom to move it in the opposite direction,substantially as described.

3; The combination in an air-brake system of a pump and pump-operatingmechanism, .a compound air-cylinder comprising two cylfinders-ofdiliferent diameters, apiston within; said compound: cylinder havingheads of ditterent: diameters corresponding with the ,bores of saidcompound: cylinder,.a valve- .chamber haying opencommunication with thesmaller of s-aid1 cylinders and having a iport connectingwith the alarger of said cylinders, an exhaust-port and means for controlling-saidports whereby'air is exhausted from the larger cylinder to allow thepistonitormove in one direction, and is-admitted to said cylindertomovethe piston in the opposite direction, snbstantialty asdescribed.

In testimony whereof I have signed my nametothiszspeoilicatiom in thepresence of two subscribingwitnesses JOHN J. NEE;

Witnesses:

CHARLES G; STEVENSON, J G. CHaABIN.

